After five days of blackouts in a large area of downtown Calgary caused by explosions and fires last autumn, the city will spend $1 million to upgrade its aging street lights.
When a suspicious relay reaches three endpoints-
Ten years of life, Transport General Manager Michael Logan said the city had no plans to replace equipment so far unless they failed.
"Relay fire is rare," Logan said.
"In fact, this is the only time we have ever recorded such a situation.
"Since the evening of October 11, 5,000 residents, 10,000 workers and 17 downtown districts have suffered blackouts, when residents in the area reported hearing small explosions and seeing blue flames shooting out from maintenance holes near the intersection of 8th Street and 5th Avenue in Southwest China.
A survey summary released by the fire department on Friday said that the extent of damage to the contents of the underground electrical room under the overhaul hole made it difficult to accurately identify the exact cause of the fire.
But the report concluded that the switch could be the culprit, because the fire changed regularly shortly after dark when a photocell triggered it to turn on the street light.
Field inspection also shows that the switch or contactor may be arced due to "carbon tracking or contact failure", leading to fire ignition.
It concludes that "due to equipment failure or aging, this event is likely to occur in any number of repair holes containing relays or contactors. "
"Follow-up checks of contactors with similar design and service life are recommended to minimize the possibility of such incidents in the future.
"The mercury sensor relay manufactured by Davis Control was installed in 1986 with street lights in the area," Logan said.
The U. S. -based company did not respond to Herald's inquiry about the recommended service life of the device, nor did it respond to other incidents of fire caused by similar devices.
About 10,000 relays control 90,000 street lights throughout the city.
Suburban equipment is installed on poles in weather conditions. -
Rated boxes, which are downtown, are lower-grade power utility treasuries.
Logan said all relays in the city's core will be relocated from the overhaul hole to the light pole to make it easier to access and reduce traffic interruptions.
"The nature of the equipment has changed and it's easier to maintain there," he said.
The money for this job will probably come from the new $12.
The City Council approved eight million capital applications this year, including funds to replace "aging, unsafe or critical system components to meet safety requirements" for the Calgary streetlight system.
Although a recent study suggested that the contract should not be renewed when it expires in 2016, the maintenance of the system is currently done by a subsidiary of ENMAX because of the city's "steady decline in performance". -
Public utilities owned by the company have a "historical monopoly" on fixed street lights. The zer0-
The Board's review indicated that in 2006, more than 80% of the repairs were completed in two days, but by 2013, only about 20% of the repairs were completed at the same time.
Reported that the city should consider outsourcing services to a number of suppliers in order to increase competition for better services.
"It is essential that the city identify and implement performance measures to monitor success," the commentary said.
"The contract shall also stipulate that it has not been achieved. . . Expected penalties.
"Enmax Chief Executive Gianna Manes said that the company has always had a strong maintenance plan.
"ENMAX will continue to inspect our wires and equipment in the overhaul holes and identify and process any precautions," Manes said.
Until now, Logan says, about 60 switches are replaced every year, and when they stop working, neighbors are either left in the dark or the lights are on.
Now, about 130 mercury relays under the city will be replaced in the next six months, starting with the oldest.
"We don't know why it caught fire, but we're sure it did," Logan said.
"Our first step is to remove all these relays. . . This is the quickest way to eliminate this risk.
"Well, the temptation of Calgary Herald. comTwitter.